Earphone pad

ABSTRACT

An earphone pad for use in combination with an earphone structure that has a peripheral flange around its housing for supporting an earphone pad and a circular opening in the housing for communicating acoustical vibrations from an electroacoustical transducer within the housing to the ear of a user. The earphone pad has an outer ring of resilient material which is dimensioned to sealably engage the flange on the housing and provide an outer acoustical seal therearound and an inner ring of resilient material which is dimensioned to sealably engage the periphery of the opening in the housing to provide an inner acoustical seal therearound. The inner and outer resilient rings are joined together in substantially coaxial relationship by a relatively thin annular sheet of resilient material which constitutes the ear-engaging surface of the earphone pad. An annular pad of resilient material is positioned on the inside of this earengaging surface to provide an acoustical seal between the earphone housing and the ear of the user. The outer ring of resilient material, inner ring of resilient material, and the annular ear-engaging surface that joins the two rings together are preferably a unitary, molded structure which is made of surgical silicone plastic by an injection molding operation.

United States Patent Kliewer [54] EARPHONE PAD [72] Inventor: Donald L.Kliewer, Minneapolis, Minn.

[73] Assignee: The Telex Corporation, Tulsa, Okla.

[22] Filed: Oct. 1, 1970 [21] Appl. N0.: 77,174

Primary ExaminerStephen .l. Tomsky AttorneyCarlsen, Carlsen & Sturm 5]Feb. 29, 1972 [57] ABSTRACT An earphone pad for use in combination withan earphone structure that has a peripheral flange around its housingfor supporting an earphone pad and a circular opening in the housing forcommunicating acoustical vibrations from an electroacoustical transducerwithin the housing to the ear of a user. The earphone pad has an outerring of resilient material which is dimensioned to sealably engage theflange on the housing and provide an outer acoustical seal therearoundand an inner ring of resilient material which is dimensioned to sealablyengage the periphery of the opening in the housing to provide an inneracoustical seal therearound, The inner and outer resilient rings arejoined together in substantially coaxial relationship by a relativelythin annular sheet of resilient material which constitutes theear-engaging surface of the earphone pad. An annular pad of resilientmaterial is positioned on the inside of this ear-engaging surface toprovide an acoustical seal between the earphone housing and the ear ofthe user. The outer ring of resilient material, inner ring of resilientmaterial, and the annular ear-engaging surface that joins the two ringstogether are preferably a unitary, molded structure which is made ofsurgical silicone plastic by an injection molding operation.

8 Claims, 4 Drawing Figures PATENTEDFEB29 I972 FIG.

INVENTOR. 004/440 4. Kt/E'll/ER EARPIIONEPAD BACKGROUND OF THE INVENTIONThis invention relates to earphone pads for protecting the ear of anearphone user and for providing an acoustical seal therearound. Moreparticularly, this invention relates to earphone pads for use incombination with audiometric earphones such as used pads for use incombination with audiometric earphones such as used in testing hearingor in other applications that require accurate calibration of acousticalvolume.

In audiometric testing, a persons hearing ability is tested by means ofa variable audiofrequency generator and a headset for translating theelectrical output of the audiofrequency generator into audible sound.The audiofrequency generator is calibrated both in terms of volume andfrequency. During the testing process, tones of different frequency areapplied to the headset and varied in volume until the subjects thresholdof hearing has been determined for selected frequencies that cover theentire audiofrequency spectrum. These threshold levels are plotted on agraph as they are measured, and by comparing the subjects graph to theaverage graph for the same age group, it is possible to detect a hearingdeficiency and to prescribe an appropriate hearing aid for remedyingthat particular deficiency.

Since the above-noted graphs are plotted in terms of acoustical volume,it is particularly important in audiometric testing to provide a tightacoustical seal between the audiometric headset and the ears of thesubject being tested so as to avoid loss of acoustical energy, whichwould introduce errors into the recorded data, and to block outbackground noise, which would affect the threshold of hearing. Inaddition, it is equally important that such a tight acoustical seal beachieved without uncomfortable pressure on the subject's ear.Accordingly, the principal object of this invention is to provide asimple, inexpensive earphone pad that meets the abovenoted requirements.

SUMMARY OF THE INVENTION In accordance with this invention, theabove-noted objective is achieved by providing an outer ring ofresilient material which is dimensioned to sealably engage a peripheralflange on the earphone housing and provide an outer acoustical sealtherearound and an inner ring of resilient material which is dimensionedto sealably engage the periphery of an acoustical outlet opening in theearphone housing to provide an inner acoustical seal therearound. Theinner and outer rings of resilient material are joined together insubstantially coaxial relationship by a relatively thin annular sheet ofresilient material which constitutes the ear-engaging surface of theearphone pad. An annular pad of resilient material is positioned on theinside of this ear-engaging surface to provide an acoustical sealbetween the earphone housing and the ear of the user. The outer ring ofresilient material, inner ring of resilient material, and the annularear-engaging surface that joins the two rings together are preferably aunitary, molded structure which is made of surgical silicone plastic byan injection molding operation.

The detailed structure and operation of the invention is described belowin connection with one specific embodiment thereof as illustrated in theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of oneillustrative earphone pad of this invention.

FIG. 2 is a cross-sectional view taken on the plane 2-2 of FIG. 1.

FIG. 3 is a perspective view of the embodiment of FIGS. 1 and 2 mountedon an earphone transducer housing.

FIG. 4 is a cross-sectional view of the embodiment of FIGS. 1 and 2mounted on an earphone transducer and held against a users ear.

DETAILED DESCRIPTION OF THE INVENTION The earphone pad of this inventionis adapted to be used in combination with an earphone structure that hasa peripheral flange around its housing for supporting an earphone padand a circular opening in the housing for communicating acousticalvibrations from an electroacoustical transducer within the housing tothe ear of the user. This is the normal configuration for earphonestructures except in spacial cases where the earphone pad is made anintegral part of the earphone structure. Referring to the figures, oneillustrative embodiment of the invention comprises an outer ring ofresilient material 10 which is dimensioned to sealably engage theperipheral flange on the earphone housing to provide an outer acousticalseal therearound and an inner ring of resilient material 12 which isdimensioned to sealably engage the periphery of the circular opening inthe earphone housing to provide an inner acoustical seal therearound.Outer ring 10 and inner ring 12 are joined together in substantiallycoaxial relationship by a relatively thin annular sheet 14 whichconstitutes the ear-engaging portion of the earphone pad. Outer ring 10,inner ring 12, and annular sheet 14 are joined together in a unitarystructure and are preferably made of surgical silicone plastic by aninjection molding operation. An annular pad of spongy, resilientmaterial 16 is positioned on the inside surface of annular sheet 14 toprovide an acoustical seal between the earphone housing and the ear ofthe user. The outside diameter of annular pad 16 is larger than theinside diameter of outer ring 10 so that the pad 16 will be held inplace by abutment against the inside periphery of outer ring 10.

As best shown in FIG. 2, outer ring 10 is adapted to sealably engage aperipheral flange on the earphone housing by means of a recessed portion18 which is slightly smaller in diameter than the outside diameter ofthe earphone flange and an inwardly flanged end 20 which issubstantially smaller in diameter than the outside diameter of theearphone flange. Inner ring 12 is adapted to sealably engage theperiphery of the circular opening in the earphone housing by means of arecessed portion 22 which is slightly smaller in diameter than thecircular opening and an outwardly flanged end 24 which is substantiallysmaller in diameter than the circular opening. FIGS. 3 and 4 show theabove-noted earphone pad fitted in place on an earphone structureincluding an earphone housing 26 which has a substantially flat endplate 28 with a central opening therein for transmitting acousticalenergy from an electroacoustic transducer 30 within the housing to theear of the user and a peripheral flange 32 around the edge of housing 26for receiving and supporting the earphone pad. As best shown in FIG. 4,the earphone pad of this invention provides three acoustical seals forpreventing loss of acoustical energy and for blocking the entry ofbackground noise into the ear of the user. The combination of the thinannular sheet 14 and annular pad 16 provides a comfortable, contoured,acoustic seal with the ear of the user. In order to provide the bestacoustic seal, the outside diameter of outer ring 20 should besuffciently large to completely cover the outer ear of an average user.It will be noted in FIGS. 3 and 4 that the engagement between inner ring12 and the opening in the earphone housing produces a convexconfiguration in the ear-engaging surface 14 which fits into the earcavity of the user and provides a better acoustical seal than could beobtained with a flat earengaging surface.

In addition to the acoustical seal around the ear of the user, theearphone pad of this invention also provides an inner acoustical sealbetween inner ring 12 and the opening in the earphone housing to preventacoustical energy from being transmitted into the interior of theearphone pad and to prevent background noise from being transmitted fromthe inte rior of the earphone pad to the users ear canal. Thus the innerring 12 performs the dual purpose of improving the acoustical sealingability of the ear-engaging surface 14 and also providing an internalacoustical seal around the opening in the earphone housing. The escapeof acoustical energy, and the introduction of background noise, isfurther minimized by the outer acoustical seal provided between outerresilient ring and the peripheral flange 32 on earphone housing 26.

From the foregoing description it will be apparent that this inventionprovides a simple, inexpensive earphone pad for providing a tightacoustical seal between an earphone housing and the ear of a userwithout requiring uncomfortable pressure on the users ear. And althoughthis invention has been described in connection with one specificembodiment thereof, it should be understood that the invention is notlimited to the disclosed embodiment since many modifications can be madein the disclosed structure without departing from the basic principle ofthis invention. For example, although the annular pad of spongyresilient material 16 is disclosed as being held in position bymechanical pressure, it could be ccmented in place if desired. Inaddition, although the disclosed embodiment is preferably made ofsurgical silicone plastic, other resilient materials could be used ifdesired. These and many other modifications will be apparent to thoseskilled in the art and this invention includes all modifications fallingwithin the scope of the following claims.

lclaim:

1. An earphone pad for use in combination with an earphone structureincluding a housing member, an electroacoustic transducer mounted withinsaid housing member, a substantially circular opening in one side ofsaid housing member for communicating acoustical vibrations from withinsaid electroacoustic transducer to the ear of a user, and asubstantially circular flange around the periphery of said housingmember for receiving and supporting an earphone pad to protect the earof a user and to form an acoustic seal therearound, said earphone padcomprising an outer ring of resilient material and an inner ring ofresilient material which are joined together in substantially coaxialrelationship by a relatively thin annular sheet of resilient material,said outer ring of resilient material being dimensioned to sealablyengage said flange to secure said earphone pad to said housing and toprovide an outer acoustical seal therearound, said inner ring ofresilient material being dimensioned to sealably engage the innerperiphery of said opening in the side of said housing to provide aninner acoustical seal therearound, and an annular pad of resilientmaterial positioned between said outer and inner resilient rings on theside of said annular sheet of resilient material which faces saidhousing for providing an acoustical seal between said housing and theouter ear of a user.

2. The earphone pad of claim 1 wherein said outer resilient ringcontains a circular recess which is dimensioned to engage the outsideperiphery of said flange in said housing and an inwardly flanged endsurrounding said circular recess which is dimensioned to engage theouter edge of said flange in said housing to secure said outer resilientring to said housing.

3. The earphone pad of claim 2 wherein said circular recess is slightlysmaller in diameter than said flange so as to fit snugly over saidflange and provide an acoustical seal therearound.

4. The earphone pad of claim 3 wherein said inner resilient ringcontains a circular recess which is dimensioned to engage the peripheryof said opening in said housing and an outwardly flanged end surroundingsaid circular recess which is dimensioned to engage the inner surface ofsaid housing around-said opening to secure said inner resilient ring tosaid housing.

5. The earphone pad of claim 4 wherein said circular recess in saidinner resilient ring is slightly smaller in diameter than said openingin said housing so as to fit snugly around the periphery of said openingand provide an acoustical seal therearound.

6. The earphone pad of claim 1 wherein said inner resilient ring, outerresilient ring, and relatively thin annular sheet of resilient materialcomprise a unitary molded structure.

7. The earphone pad of claim 6 wherein said inner resilient ring, outerresilient ring, and relatively thin annular sheet of resilient materialcomprise a unitary molded structure made of surgical silicone plastic.

. The earphone pad of claim 1 wherein said annular pad of resilientmaterial comprises an annular pad of surgical silicone sponge material.

1. An earphone pad for use in combination with an earphone structureincluding a housing member, an electroacoustic transducer mounted withinsaid housing member, a substantially circular opening in one side ofsaid housing member for communicating acoustical vibrations from withinsaid electroacoustic transducer to the ear of a user, and asubstantially circular flange around the periphery of said housingmember for receiving and supporting an earphone pad to protect the earof a user and to form an acoustic seal therearound, said earphone padcomprising an outer ring of resilient material and an inner ring ofresilient material which are joined together in substantially coaxialrelationship by a relatively thin annular sheet of resilient material,said outer ring of resilient material being dimensioned to sealablyengage said flange to secure said earphone pad to said housing and toprovidE an outer acoustical seal therearound, said inner ring ofresilient material being dimensioned to sealably engage the innerperiphery of said opening in the side of said housing to provide aninner acoustical seal therearound, and an annular pad of resilientmaterial positioned between said outer and inner resilient rings on theside of said annular sheet of resilient material which faces saidhousing for providing an acoustical seal between said housing and theouter ear of a user.
 2. The earphone pad of claim 1 wherein said outerresilient ring contains a circular recess which is dimensioned to engagethe outside periphery of said flange in said housing and an inwardlyflanged end surrounding said circular recess which is dimensioned toengage the outer edge of said flange in said housing to secure saidouter resilient ring to said housing.
 3. The earphone pad of claim 2wherein said circular recess is slightly smaller in diameter than saidflange so as to fit snugly over said flange and provide an acousticalseal therearound.
 4. The earphone pad of claim 3 wherein said innerresilient ring contains a circular recess which is dimensioned to engagethe periphery of said opening in said housing and an outwardly flangedend surrounding said circular recess which is dimensioned to engage theinner surface of said housing around said opening to secure said innerresilient ring to said housing.
 5. The earphone pad of claim 4 whereinsaid circular recess in said inner resilient ring is slightly smaller indiameter than said opening in said housing so as to fit snugly aroundthe periphery of said opening and provide an acoustical sealtherearound.
 6. The earphone pad of claim 1 wherein said inner resilientring, outer resilient ring, and relatively thin annular sheet ofresilient material comprise a unitary molded structure.
 7. The earphonepad of claim 6 wherein said inner resilient ring, outer resilient ring,and relatively thin annular sheet of resilient material comprise aunitary molded structure made of surgical silicone plastic.
 8. Theearphone pad of claim 1 wherein said annular pad of resilient materialcomprises an annular pad of surgical silicone sponge material.